21 research outputs found
A conceptual model for sheet-flow drawn from rapid granular flow theories
33rd IAHR Congress: Water Engineering for a Sustainable EnvironmentThis paper is aimed at presenting i) a simple, yet sound, conceptual model applicable
to the simulation of erosion, deposition and transport of cohesionless
sediment in stratified flows under high shear stresses and ii) numerical solutions
in idealized unsteady flow non-equilibrium transport situations. The conceptual
model for the granular phase comprises 2DV mass and momentum and energy
equations and constitutive equations, all derived within the dense limit of the
Chapman-Enskog kinetic theory. 1D shallow-flow conservation and closure equations
are derived for the fluid-granular mixture. Formulas for the average velocity
in the transport layers, the vertical net flux of sediment mass and the thickness of
the transport layer are thus obtained. Numerical solutions for dam-break flows
over cohesionless mobile beds in prismatic and non-prismatic channels are obtained
and discussed
Genome-wide association and HLA fine-mapping studies identify risk loci and genetic pathways underlying allergic rhinitis
Allergic rhinitis is the most common clinical presentation of allergy, affecting 400 million people worldwide, with increasing incidence in westernized countries1,2. To elucidate the genetic architecture and understand the underlying disease mechanisms, we carried out a meta-analysis of allergic rhinitis in 59,762 cases and 152,358 controls of European ancestry and identified a total of 41 risk loci for allergic rhinitis, including 20 loci not previously associated with allergic rhinitis, which were confirmed in a replication phase of 60,720 cases and 618,527 controls. Functional annotation implicated genes involved in various immune pathways, and fine mapping of the HLA region suggested amino acid variants important for antigen binding. We further performed genome-wide association study (GWAS) analyses of allergic sensitization against inhalant allergens and nonallergic rhinitis, which suggested shared genetic mechanisms across rhinitis-related traits. Future studies of the identified loci and genes might identify novel targets for treatment and prevention of allergic rhinitis